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21.
Labour contracting is anywhere on the rise globally, even in fully developed capitalist countries. Far from being an anomaly in the smooth everyday functioning of the economy, contractors are a crucial node in facilitating and ensuring global capital's control over local labour regimes. This article uses a global value chain perspective to investigate the re‐emergence of gangmasters and gang labour in the agricultural sector of Lazio, Central Italy. It analyses the fruit and vegetable supply chain formation and configuration in the Lazio Region with the aim of identifying the underlying processes leading to the creation of gangmasters by capital to have a cheap and disposable, especially migrant, labour force. It also intends to give a more nuanced understanding of labour contracting in this context.  相似文献   
22.
选取2005-2016年285个地级及以上城市数据,利用静态和动态短面板模型分析经济密度和人口规模对环境污染的影响,分析表明:经济密度与环境污染之间存在“倒U型”关系,人口规模扩大会抑制污染物排放;不同等级城市经济密度、不同规模城市人口对环境污染的影响方向一致,但影响程度有所差异;前期污染排放对当期具有正向影响,环境污染物排放存在路径依赖;经济发展水平、工业产值占比和对外开放也是影响污染物排放的重要因素,但各指标对三类污染物排放的影响方向和影响程度存在差异。据此认为,在综合考虑城市具体空间区位条件下,人口适度集聚,提高城市经济密度,优化产业结构以及加强环境监管是环境治理的重要方向。  相似文献   
23.
Algorithmic traders use their advantage of speed to execute a large number of small-sized trades in a very short time. In the presence of a minimum trading unit (MTU) restriction, they are forced to trade at the smallest possible sizes, often restricted by the MTU. Using a novel data set of single stock futures market obtained from the National Stock Exchange of India, we show that the MTU restriction acts as a binding constraint for traders while optimizing trade sizes. Contrary to expectation, we find weak evidence that liquidity is positively impacted by the contract size revision.  相似文献   
24.
This paper investigates the extent to which access to credit, public financial incentives and tax financial incentives affect export performance using the EU-EFIGE/Bruegel-Unicredit data set, covering firms within Austria, France, Germany, Italy, Spain, Hungary and the UK during the 2008 global financial crisis. The results show that firms receiving credit or benefiting from public financial incentives display higher export intensity and export a greater number of product lines compared to those that did not, especially in countries with better access to credit and/or financial incentives during the crisis. Further, firms benefiting from tax financial incentives show a better export performance compared to those that did not, regardless of the degree of access to credit and/or financial incentives in the country in which they operate. In addition, the effect of access to credit and public finance incentives on export performance is found to be size-dependent, while the effect of tax financial incentives is not. We suggest that governments should promote publicly funded financial incentives along with conventional schemes, such as R&D subsidies, to promote exports, particularly during a period of financial crisis.  相似文献   
25.
To improve the economies of scale in forest management and reduce the fragmentation of forestland, the Chinese central government has implemented a collective forest tenure supplementary reform since 2008. This has included a series of policies for motivating transfer of forestlands use rights among households in the country’s Southern Collective Forest Area (SCFA). However, to date there is little evidence that large-scale forest owners can earn more profits from timber harvests than small-scale forest owners in the SCFA. Using data collected from household surveys in the three of the SCFA’s provinces in 2016, this paper examines the return to scale of forestland ownership for timber harvests in this region, and how the scale of forestland ownership affects households’ profits from timber harvests. The results show a constant return to scale in timber harvests in the case provinces in China’s SCFA, that forestland area makes the most important contribution to the output of timber harvests, and that fragmentation of forestland results in lower profits from timber harvests. It appears that a moderate scale of forestland ownership should be identified for increasing the profits from timber harvests. With the rapid urbanization throughout China, an increase in off-farm employment among rural household members has a negative impact on timber harvests in the region. We argue that policymakers should realize the importance of encouraging the forestland transfers and improve the concentration of forestlands in the next stage of forest tenure rights reform in China’s SCFA.  相似文献   
26.
车辆类型识别方法是智能交通系统的关键技术之一。利用深度学习的高维特征泛化学习能力,将改进的LeNet-5卷积神经网络用于基于交通微波雷达的大小车型分类识别。首先,以雷达触发前的N帧信号为基础,对雷达的回波信号进行分析并构建数据集;然后,分析LeNet-5卷积神经网络的特点;最后提出一种改进的LeNet-5卷积神经网络。实验结果表明,与传统的支持向量机方法相比,所提方法能够智能学习大小车的雷达时频信号特征,大小车型识别准确率达到97%以上,可为交通场景下的车型识别研究提供新的技术途径。  相似文献   
27.
Intercropping, i.e. the cultivation of crop species mixtures, can potentially reduce pressure on land resources by generating higher yields through exploitation of complementarities between crop species. Although intercropping is practiced on a non-negligible proportion of China’s arable land, little is known about the factors that influence farmers’ decisions to use intercropping. In this study we develop a theoretical framework that distinguishes exogenous factors from endogenous factors in farmers’ activity choices in general and the use of intercropping in particular. We apply this framework in an empirical analysis of socio-economic factors affecting the use of traditional and novel relay intercropping systems, with a special focus on the impact of farm size, using primary data collected among 299 farmers in Gaotai County, northwest China. We find that large farms do no not plant more land with the traditional wheat/maize intercrop as compared to small farms, while land planted with the two novel intercrops is significantly larger on large farms. Availability of machinery has no negative effect on the area under intercropping, and has a significant positive effect on the use of one novel intercrop type. Our results confirm that risk considerations do not play a role in relay intercropping use decisions of Chinese farmers. We conclude that positive yield and natural resource effects of intercropping can still be realized if the ongoing farm scale enlargement policy is combined with a policy promoting novel intercropping types, particularly those types that can make use of already available machinery.  相似文献   
28.
Accelerators are a recent yet rapidly growing phenomenon within entrepreneurial ecosystems. The distinctive characteristics exhibited by accelerators, relative to previous incubation models, imply that accelerators may play a different role and have a different impact on the survival rates of participating firms. In this study, we explore the relationship between participation in an accelerator program and firm survival using fuzzy-set qualitative comparative analysis (fsQCA) with key variables related to firm survival. We analyze 38 accelerated startups from five Italian accelerators and a control group of 38 non-accelerated Italian startups. Our findings support the business accelerator literature that regards accelerators as a new and distinct generation of business incubators. Our results suggest that participation in accelerator programs on its own does not influence firm survival. However, we found a relationship between firm survival and accelerated technology-based firms that do not export and between firm survival and accelerated firms in the service sector with a small team that do not export. We conclude that factors affecting the survival of accelerated firms are different from factors affecting the survival of incubated firms, providing further evidence of the characteristics that distinguish accelerators from incubators.  相似文献   
29.
This article reviews the past and potential future roles of land tenure reforms and land markets in Sub-Saharan Africa (SSA) as responses to population growth in the process of land use intensification and livelihood transformation. The farm size distribution and the existence of an inverse relationship (IR) between farm size and land productivity in SSA and the implications of this relationship for efficiency and equity are investigated. More secure property rights and removal of restrictions on land markets have the potential to create both efficiency and equity benefits, but there are high risks of elite capture of large land areas with inefficient and inequitable outcomes. This situation is the case not only in land-abundant areas but also in urban and peri-urban areas where increasingly larger proportions of people will make their living. Increasing population pressure in densely populated rural areas contributes to more rapid rural–urban migration, and creating alternative livelihood opportunities for the migrating youth population is essential to achieving economic development with social stability.  相似文献   
30.
Evidence assembled in this special issue of Food Policy shows that rising rural population densities in parts of Africa are profoundly affecting farming systems and the region’s economies in ways that are underappreciated in current discourse on African development issues. This study synthesizes how people, markets and governments are responding to rising land pressures in Africa, drawing on key findings from the various contributions in this special issue. The papers herein revisit the issue of Boserupian agricultural intensification as an important response to land constraints, but they also go further than Boserup and her followers to explore broader responses to land constraints, including non-farm diversification, migration, and reduced fertility rates. Agricultural and rural development strategies in the region will need to more fully anticipate the implications of Africa’s rapidly changing land and demographic situation, and the immense challenges that mounting land pressures pose in the context of current evidence of unsustainable agricultural intensification, a rapidly rising labor force associated with the region’s current demographic conditions, and limited nonfarm job creation. These challenges are manageable but will require explicit policy actions to address the unique development challenges in densely populated rural areas.  相似文献   
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